The Faceless Fish of the Deep, Deep Sea

Line drawing of a Faceless Cusk, Typhlonus nasus, drawn in 1886 by Albert Gunther. Credit: Public domain.

They didn’t know what they would find when they set off for a month at sea on May 15, 2017. But when 40 scientists returned from trawling the deepest waters off the coast of Australia, they had a haul that would make Charles Darwin, the adventurous explorer of the Galapagos Islands, envious. Among meat-eating sponges, flesh-eating crustaceans, zombie worms, blind sea spiders and a toothy dragonfish to haunt your nightmares, scientists found a fish without a face.

The scientists called their mission Sampling the Abyss, and that’s exactly what they did. They pulled up whatever they could from 2.5 miles below the surface, using sleds, grabs, and nets. The unusual fish they found didn’t seem to have eyes or any other facial features. Closer investigation revealed that it had tiny eyes on the underside of its head, where its mouth was, but they were buried under the skin. The expedition’s chief scientist, Tim O’Hara from Australia’s Museums Victoria, expects it has very poor eyesight and relies instead on sensory organs in its jelly-like head to survey its environment.

The team sent tissue samples to experts for analysis and learned their faceless swimmer was discovered during the Voyage of HMS Challenger, the first global oceanographic expedition, in the Coral Sea in 1874, just 9 years before Darwin died. Its scientific name, Typhlonus nasus, means “blind hake,” but it’s actually a type of cusk eel. The Australian scientists have named it the Faceless Cusk. Remarkably, these fish live across a wide range of the deep, deep sea, including Indonesia, Papua New Guinea, Japan, Hawaii and the Arabian Sea. Scientists don’t know much more about it—or their other catches—yet. But they have plenty of time to learn more about all these new mysteries of the deep.